curl/docs/libcurl/curl_ws_recv.3

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.TH curl_ws_recv 3 "12 Jun 2022" "libcurl" "libcurl"
.SH NAME
curl_ws_recv - receive WebSocket data
.SH SYNOPSIS
.nf
#include <curl/easy.h>

CURLcode curl_ws_recv(CURL *curl, void *buffer, size_t buflen,
                      size_t *recv, const struct curl_ws_frame **meta);
.fi
.SH DESCRIPTION
This function call is EXPERIMENTAL.

Retrieves as much as possible of a received WebSocket data fragment into the
\fBbuffer\fP, but not more than \fBbuflen\fP bytes. \fIrecv\fP is set to the
number of bytes actually stored.

If there is more fragment data to deliver than what fits in the provided
\fIbuffer\fP, libcurl returns a full buffer and the application needs to call
this function again to continue draining the buffer.

The \fImeta\fP pointer gets set to point to a \fIconst struct curl_ws_frame\fP
that contains information about the received data. See the
\fIcurl_ws_meta(3)\fP for details on that struct.
.SH EXAMPLE
.nf
  size_t rlen;
  const struct curl_ws_frame *meta;
  char buffer[256];
  CURLcode result = curl_ws_recv(curl, buffer, sizeof(buffer), &rlen, &meta);
.fi
.SH AVAILABILITY
Added in 7.86.0.
.SH RETURN VALUE
Returns \fBCURLE_OK\fP if everything is okay, and a non-zero number for
errors. Returns \fBCURLE_GOT_NOTHING\fP if the associated connection is
closed.

Instead of blocking, the function returns \fBCURLE_AGAIN\fP. The correct
behavior is then to wait for the socket to signal readability before calling
this function again.
.SH "SEE ALSO"
.BR curl_easy_setopt "(3), " curl_easy_perform "(3), "
.BR curl_easy_getinfo "(3), "
.BR curl_ws_send "(3), "  libcurl-ws "(3), "